Insight into the Internal Structure of High-Performance Multicore Magnetic Nanoparticles Used in Cancer Thermotherapy - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue ACS Materials Au Année : 2024

Insight into the Internal Structure of High-Performance Multicore Magnetic Nanoparticles Used in Cancer Thermotherapy

Dalila Miele
  • Fonction : Auteur
Giuseppina Sandri
  • Fonction : Auteur
Felista Tansi-Lemnyui
  • Fonction : Auteur
Frank Steiniger
  • Fonction : Auteur
Paul Southern
  • Fonction : Auteur
Quentin Pankhurst

Résumé

Multicore magnetic nanoparticles (MNPs), comprising iron oxide cores embedded in a sugar or starch matrix, are a class of nanomaterials with promising magnetic heating properties. Their internal structure, and particularly the strength of the internal core-core magnetic interactions, are believed to determine the functional properties, but there have been few detailed studies on this to date. We report here on an inter-laboratory and multi-modality transmission electron microscopy (TEM) and magnetic study of a high-performance MNP material (supplied by Resonant Circuits Limited, RCL) that is currently being used in a clinical study for the treatment of pancreatic cancer. TEM data were collected under a variety of conditions: conventional; high-resolution; scanning; cryogenic; and, for the first time, liquid-phase. All the imaging modes showed mostly irregular dextran lamellae of lateral dimensions 30-90 nm, plus ca. 15% n/n of what appeared to be 30-60 nm long “nanorods”, and a multitude of well-dispersed ca. 3.7 nm diameter iron oxide cores. Cryogenic electron tomography indicated that the nanorods were edge-on lamellae, but in dried samples, tomography showed rod- or lath-shaped forms, possibly resulting from the collapse of lamellae during drying. HRTEM showed the dextran to be crystallized in the low-temperature hydrated dextran polymorph. Magnetic remanence Henkel-plot analysis indicated a weak core-core interaction field of ca. 4.8 kA/m. Theoretical estimates using a point-dipole model associated this field with a core-to-core separation distance of ca. 5 nm, which tallies well with the ca. 4-6 nm range of separation distances observed in liquid-cell TEM data. On this basis we identify the structure-function link in the RCL nanoparticles to be the unusually well-dispersed multicore structure that leads to their strong heating capability. This insight provides an important design characteristic for the future development of bespoke nanomaterials for this significant clinical application

Domaines

Chimie
Fichier principal
Vignette du fichier
Manuscript Roussel PDF.pdf (6.04 Mo) Télécharger le fichier
Origine Fichiers produits par l'(les) auteur(s)

Dates et versions

hal-04622011 , version 1 (24-06-2024)

Identifiants

  • HAL Id : hal-04622011 , version 1

Citer

Tom Roussel, Daniel Ferry, Artemis Kosta, Dalila Miele, Giuseppina Sandri, et al.. Insight into the Internal Structure of High-Performance Multicore Magnetic Nanoparticles Used in Cancer Thermotherapy. ACS Materials Au, 2024. ⟨hal-04622011⟩
0 Consultations
0 Téléchargements

Partager

Gmail Mastodon Facebook X LinkedIn More